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991.
The surgical outcomes of 13 patients who were diagnosed with cervical spondylotic myelopathy were reviewed retrospectively. Mean patient age at surgery was 83 years. The severity of cervical spondylotic myelopathy was evaluated using the Japanese Orthopaedic Association score. Daily activities were evaluated using the Barthel index. The preoperative JOA score and Barthel index were 7.8 and 63.5, respectively. The mean JOA score and Barthel index maximum recovery rate were 35% and 24%, respectively. The results of this study imply that surgery for patients with cervical spondylotic myelopathy aged > 80 years is warranted.  相似文献   
992.
Nishikawa M  Ohata K  Baba M  Terakawa Y  Hara M 《Neurosurgery》2004,54(6):1430-4; discussion 1434-5
OBJECTIVE AND IMPORTANCE: We describe an alternative surgical technique for treatment of Chiari I malformation associated with ventral compression and instability of the region. An expansive suboccipital cranioplasty and a rigid occipitocervical fixation are performed in one stage. METHODS: The occipitocervical fixation is performed by use of metal rods fixed on the cranial side by screws inserted into the diploic layer of occipital bone and on the caudal side by screws inserted into the pedicle of the axis or in a transarticular fashion into the lateral masses of axis and atlas vertebra. A large piece of autologous bone is placed in the region between the rostral edge of cranial decompression and the axis, with the aim of achieving both expansive suboccipital cranioplasty and occipitocervical fusion. RESULTS: We performed this procedure in two patients with Chiari I malformation associated with basilar invagination and occipitalization of the atlas. Postoperatively, decompression of the brainstem and restoration of normal cerebrospinal fluid flow at the craniovertebral junction were confirmed radiologically, and the patients were relieved of their symptoms. At 1 and 3 years of follow-up, respectively, solid bone fusion was observed between the occipital bone and axis in both patients. CONCLUSION: Simultaneous posterior decompression and occipitocervical fixation with an alternative instrumentation technique is discussed. The procedure can be performed regardless of the size of suboccipital craniectomy. Screw insertion into the diploic layer of the occipital bone has not been described previously.  相似文献   
993.
We have created an alternative method for tracheal reconstruction. Our new surgical procedure using a deltopectoral flap combined with a costal cartilage graft and mucosal graft for tracheal reconstruction allows us to achieve reconstruction of the tracheal mucosa, the tracheal cartilage, and the covering skin with adequate subcutaneous tissue. In one case, a tracheostenosis was reconstructed with a deltopectoral flap combined with a costal cartilage graft. In the other case, a tracheal defect was reconstructed with a deltopectoral flap combined with a costal cartilage graft and palatal mucosal graft. Although the operation is a multistage procedure, our method provides satisfactory clinical results. Thus, we believe that our method is useful for the surgical treatment of large tracheal defects.  相似文献   
994.
Oki H  Ando M  Omori H  Okumura Y  Negoro K  Uchida K  Baba H 《Artificial organs》2004,28(11):1050-1054
In acetabular dysplasia, more vertical orientation of the acetabular component is often used to minimize the superolateral bone grafting. This study was designed to determine the effects of vertical orientation of the cup on the stability and polyethylene wear of the acetabular component in uncemented total hip arthroplasty (THA). Three-dimensional finite element models of the hemipelvis with dysplastic acetabulum were developed. Metal-backed hemispherical cups were placed in the true acetabulum with abduction angles of 35, 45, 55, and 65 degrees. It was found that more vertical orientation of the cup was associated with larger relative motion of the metal shell between the acetabulum and metal shell. Furthermore, tilting and torsional shear stresses in the model of the cup abduction angle of 65 degrees were found to be 1.7 times larger than that in the model with 35 degrees at the bone-metal shell interface. More vertically oriented cups caused larger contact stresses at the articulating surfaces of the polyethylene liners. The results suggest that the abduction angle of the acetabular component significantly influences cup loosening and polyethylene wear in THA.  相似文献   
995.
We report a case of isolated brain stem injury caused by the tentorium cerebelli. A 17-year-old male was admitted to our hospital. Thirty minutes before admission, he was struck by another motorcycle while driving his own motorcycle. The Glasgow Coma Scale (GCS) was 10. He had no extremity weakness and his pupils were normal. CT scan showed no evidence of intracranial lesions except for facial bone fractures. His consciousness level improved to GCS 13 at 6 hours after admission. Follow-up CT scan was normal, however MRI 3 days after admission showed a contusion at the left lateral midbrain. He was discharged without any neurological deficits on 6 days after admission. Analysis of the distance between the brain stem and the tentorial margin using MR cisternography showed that the left side was shorter than the right side. We presumed that an isolated lateral brain stem injury was caused by the direct impact of the tentorium cerebelli. Typically the location of this type of lesion is present in the same side as that of impact. However in this case the orientation was opposite to that. We considered that the distance between the brain stem and the tentorial margin affected the mechanism of this lesion.  相似文献   
996.
997.
PURPOSE: The efficacy of external-beam radiation therapy (RT) was evaluated in the treatment of eyes with subfoveal or juxtafoveal choroidal neovascularization in age-related macular degeneration (ARMD). MATERIALS AND METHODS: Twenty-one eyes of 18 patients with occult or mixed-type ARMD received a total dose of 20 Gy of 6 MV X-rays in 10 fractions. The follow-up time was 24 months. Fifteen non-treated eyes of 13 patients who had been followed served as a control. RESULTS: In the RT group, visual acuity was improved in three eyes, maintained in 14 eyes, and worsened in four eyes. In the control group, it was not improved in any eyes, was maintained in six eyes, and worsened in nine eyes. The improved or maintained rate in visual acuity was 81% in the RT group and 40% in the control group (p=0.0342). In the RT group, fundoscopic and angiographic findings were improved in five eyes, unchanged in seven eyes, and worsened in nine eyes, while they were not improved in any eyes, unchanged in two eyes, and worsened in 13 eyes in the control group(p=0.0342). CONCLUSION: RT at a total dose of 20 Gy in 10 fractions is effective for ARMD for at least two years. RT may be effective treatment for occult or mixed-type ARMD compared with the classic type.  相似文献   
998.
The hepatic falciform artery is a small vessel that arises as a terminal branch of the middle or left hepatic artery. Its anatomy and clinical importance have been described in several recent reports. During dissection of a cadaver, this artery is generally found connected with the ensiform branch of the internal mammary artery. However, to our knowledge, anastomosis has not previously been described radiologically.  相似文献   
999.
OBJECTIVE: Recent animal PET research has led to the development of PET scanners for small animals. A planar positron imaging system (PPIS) was newly developed to study physiological function in small animals and plants in recent years. To examine the usefulness of PPIS for functional study in small animals, we examined dopaminergic images of mouse striata in MPTP-induced parkinsonism. METHODS: Male C57BL/6NCrj mice were treated with MPTP 7 days before the PPIS study. Scans were performed to measure dopamine D1 receptor binding and dopamine transporter availability with [11C]SCH23390 (about 2 MBq) and [11C]beta-CFT (about 2 MBq), respectively. After the PPIS study, dopamine content in the striatum was measured by HPLC. RESULTS: The MPTP treatment significantly reduced dopamine content in the striatum 7 days after treatment. In the MPTP-treated group, [11C]beta-CFT binding in the striatum was significantly decreased compared with the control group, while striatal [11C]SCH23390 binding was not affected. Dopamine content in the striatum was significantly correlated with the striatal binding of [11C]beta-CFT. CONCLUSION: The present results suggest that PPIS is able to determine brain function in a small animal. Using PPIS, high throughput imaging of small animal brain functions could be achieved.  相似文献   
1000.
BACKGROUND: Although it is well known that a no-smoking policy can reduce smoking rate among hospital employees, the effect of this policy on patients' smoking behavior has not been examined. METHODS: Starting on the world no-tobacco day in 2001, the Sakai Municipal Hospital changed partial no-smoking policy into complete no-smoking policy. In this study, we examined the effect of this policy change on patients' smoking status during preoperative period. At preoperative visit, we asked a patient a change of smoking status during preoperative period. The change of patients' smoking status was compared between before and after coming into effect of no-smoking policy. RESULTS: Smoking rates at first visit to out-patient clinic of each surgical department before and after coming into effect of no-smoking policy were 35.6%(36/101) and 41.8%(28/67), respectively (P=0.317). Among these smokers, smoking cessation rates at preoperative visit before and after coming into effect of no-smoking policy were 44.4%(16/36) and 75.0%(21/28), respectively (P=0.014). CONCLUSIONS: The hospital no-smoking policy has a strong effect on improvement of patients' smoking behavior during preoperative period.  相似文献   
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